UPDATE JANUARY 10'th 2019: Made a slight alteration to the build to allow entry/exit to both cockpits after the latest patch-change from Eleon. In the second cockpit (the "hidden" one in the middle) you now just have to make a little "skip" to get out over the edge of the shutterdoor. In the frontcockpit i removed a few blocks so one should now slide out to the side and behind the cockpit.
Both cockpits worked for me when testing it. If there is issues for you in any way, pls make a comment about it.